Radio Channel Measurements and Modeling for Indoor Millimeter-Wave Communications at 45 GHz

In recent years, the continuous development of wireless communications makes the spectrum resource available at present much more depleted. There has been mounting attention in industry and academia to study millimeter wave frequencies for short range hot spots or small cell operations in dense urban environments, and growing interest and demand in using millimeter wave bands for next generation WLAN (Wireless Local Area Networks) and mobile networks, because the frequency is relatively high, the available bandwidth can be wider, and the data rate carried can be much larger.;State Radio Regulation Bureau of China has allocated Q-band 40.5-42.3 GHz / 48.4-50.2 GHz (Point-to-Point Fixed Link) and 42.3-47.0 GHz / 47.2-48.4 GHz (Pointto- Area WLAN and Mobile Link), and V-band 59-64 GHz (WLAN) as unlicensed frequency spectrum for short range radio-communications in China. In January 2012, IEEE established a new project task group to draft the standard "IEEE Std 802.11 TGaj Enhancements for VHT to support the 40-50 GHz and 59-64 GHz Chinese mm-wave frequency bands." It is expected to be approved in the end of 2015.;Channel models are very important parameters of physical layer specifications of radio-communications. It is critical for link budget, interference mitigation, platform noise budget, components characterization, device research and development, system level simulations and network access capacity estimations in millimeter wave communication system designing, deployment, and network optimization.;Studies presented in my thesis is dedicated for substantial contributions of China 45 GHz band mm-wave wireless communications channel models to IEEE Std 802.11aj and ITU-R M.[IMT above 6 GHz]. The methodology of channel modeling is very similar for other interested millimeter bands, so applicable for outdoor cellular communications with potential millimeter wave bands.;"IEEE Std 802.11ad-2012 Enhancements for VHT (Very High Throughput) in the 60 GHz band" and "IEEE Std 802.15.3c-2009 Millimeter wave-based alternative physical layer extension" have been issued. Both standards are applicable for 57-66 GHz band. In 2014, ITU-R SG5 started to study ITU-R M.[IMT above 6 GHz] on the technical feasibility of 6-100 GHz band for International Mobile Telecommunications 2020. Requested by ITU-R SG5, ITU-R SG3 has started to study the radio propagation characteristics and channel modeling of 6-100 GHz band.;45 GHz band, which is challenging, has not been systematically studied over the world besides china. The absolute challenge for mm-wave channel models is to have a systematic channel model with adjustable parameters for all scenarios and propagation effects. A feasible one is to develop a reasonable collection of 3D channel models for the most likely indoor use case environments and scenarios.;First, the fading characteristics of mm-wave wireless communications have been investigated, including the path-loss and multi-path effect, and general approaches of radio propagation measurements and channel modeling were introduced.;Second, large amount of radio propagation measurement work at 45 GHz band has been carried out using VNA (Vector Network Analyzer) of high performance. The aim is to research large-scale and small-scale fading of most scenarios in three typical indoor environments including the conference room, the living room and the cubicle office. Abundant and reasonable data was obtained from the comprehensive and timeconsuming measurements. Serving system (sliding along x, y, and z axis lines, rotating in azimuth and elevation directions) for automatically positioning during channel measurements was designed and manufactured. For large scale modeling at 45 GHz, power gain (negative path loss) from a transmitting point (AP (Access Point) and/or STA (Station Terminal)) to each receiving points (around 10 STA points with different distances) are measured. For small scale modeling at 45 GHz, stable and repeatable amplitude-frequency data at 36 angles with a rotating step of 10 degree (both transmitting and receiving antennas) are measured. By discrete IFFT (Inverse Fast Fourier Transformation), CIR (Channel Impulse Response) with 1.5 ns time-domain resolution of small scale fading is computed. (Abstract shortened by ProQuest.).